Abstract: An apparatus for retaining a plug in a fluid end used in hydrocarbon recovery having a lock collar configured in a cylinder shape, a screw, a center hexagon configured to be inserted into the lock collar, the center hexagon configured with a port that extends along a longitudinal axis of the center hexagon, the center hexagon further configured with six sides, each of the six sides interfacing with the port, and the center hexagon further configured with a bottom face and a segmental wedge.

Abstract: A device and method for stabilizing a broken bone while it heals is disclosed. The device preferably has a (a) first (or proximal) section with a driving head, threads and a first diameter, and (b) second (or distal) section that is threaded and has a second diameter. The first section is preferably greater in diameter than the second section so that greater torque can be applied to tighten the device. The device may include one or more self-tapping structures to lessen the torque required to screw it into a bone.

Abstract: A bottom hole assembly may include a shaft having threads, a first fastener member positioned on the shaft, the first fastener member having first fastener threads that mesh with a first portion of the threads on the shaft, and a second fastener member positioned downhole of the first fastener member on the shaft, the second fastener member having second fastener threads that mesh with a second portion of the threads on the shaft, wherein the first fastener member and the second fastener member interact with each other such that an uphole face of the first fastener threads are pressed against a downhole face of the first portion of the threads on the shaft and a downhole face of the second fastener threads are pressed against an uphole face of the second portion of the threads on the shaft.

Abstract: A surgical screw according to an exemplary aspect of the present disclosure includes, among other things, a shaft portion that extends between a proximal end and a distal end, the shaft portion including a first thread having a variable pitch and a head portion extending from the proximal end of the shaft portion. The head portion includes a second thread having a pitch that is equal to a pitch of at least a portion of the variable pitch.

Abstract: A fastener for fixing bone and a method of fixing bone with the fastener. The fastener may be headless and may be configured to compress bone when driven into at least one bone and across a discontinuity formed by the bone. In an exemplary embodiment, the fastener includes a forward portion, a rear portion, a first thread having a plurality of revolutions in each of the forward and rear portions, and a second thread having a plurality of revolutions in the rear portion and none in the forward portion. The first thread may have a greater average lead in the forward portion than the rear portion. Revolutions of the first thread and the second thread may alternate with one another in the rear portion such that the rear portion is at least double-threaded.

Abstract: A cannulated bone anchor assembly includes a bone anchor, a receiver member for receiving a spinal fixation element to be coupled to the bone anchor, and a closure mechanism to fix the spinal fixation element with respect to the receiver member. The bone anchor includes a distal shaft having a first threaded section distal to a proximal head, a second threaded section distal to and adjacent the first threaded section, and a third threaded section distal to and adjacent the second threaded section. The first threaded section having a constant major and minor diameter. The second threaded section having a tapering major and minor diameter. The third threaded section having a tapering major diameter and a constant minor diameter.

Abstract: Implementations described herein include headless compression screws and corresponding systems. The headless compression screw has a shaft extending along a longitudinal axis from an insertion end to a driving end. The shaft includes a first portion and a second portion. The first portion extends from proximate the insertion end to a first intermediate point and includes a first thread extending along at least a portion thereof that has a constant pitch. The second portion extends from proximate the driving end to a second intermediate point and includes a thread extending along at least a portion thereof that has a variable pitch that decreases from a first value proximate the second intermediate point to a second value proximate the driving end. Methods of reducing a fracture using headless compression screws are also described.

Abstract: Headless compression screws are described. The headless compression screws include first and second ends coupled by a shaft, a first threaded portion positioned proximate the first end that surrounds the shaft and includes s first threads spaced apart from one another at a constant pitch, and a second threaded portion proximate the second end that surrounds the shaft and includes second threads. The second threads are spaced apart from one another at a variable pitch, such that distances between adjacent threads of the second threaded portion decrease as distance from the second end decreases. Methods of reducing a fracture using headless compression screws are also described.

Abstract: A twist-locking mechanism for two telescoping tubes, as may comprise a curtain rod, comprises a sleeve which expands outwardly as it moves along the screw of a screw body. A tapered or straight screw connects to a plain shaft portion upon which the sleeve rests when the device is in the unlock position. In another embodiment, the pitch or profile of the thread of a straight screw changes along the length of the screw, so the sleeve is forced radially outwardly as it moves from the unlock position. Split-sleeves useful in the locking mechanism have spring like features or an oblong shape, so the sleeve is biased outwardly to frictionally engage one the tube when the sleeve is at the unlock position.

Abstract: A fastener including a bolt having an elongated shank having a first end, a second end opposite the first end, and a threaded portion having an external bolt thread, the bolt thread including a bolt pitch. The fastener includes a nut having a first end, a second end opposite the first end of the nut, and an internal nut thread extending between the first and second ends of the nut and adapted to engage threadedly the bolt thread of the bolt. The nut thread includes a nut pitch and a hardness that changes gradationally between the first and second ends of the nut. The bolt pitch of the bolt thread of the bolt is mismatched with the nut pitch of the nut thread of the nut.

Abstract: A method for manufacturing a screw element (1) with a first external thread section (3) and with a second external thread section (5), wherein the screw element (1) to be manufactured is characterized in that the second external thread section (5) is positioned relative to the first external thread section (3) in such a way as to yield a braking torque when tightening the two external thread sections (3, 5) with an internal thread element (13), with the following procedural steps: the first and second external thread section (3, 5) are positioned relative to each other in such a way as to yield the braking torque while tightening the two external thread sections (3, 5) with an internal thread element (13), wherein the external thread sections (3, 5) are positioned via a defined, relative adjustment of the external thread sections (3, 5) in an axial direction and/or circumferential direction, wherein the first external thread (3) is fabricated at a compression molded first axial section (17), and the second ex

Abstract: A self-locking fastener includes a head, and a solid shaft extending from the head. The shaft includes a threaded portion away from the head. A slot is defined in the threaded portion along the axis of the threaded portion to divide the threaded portion into two parts.

Abstract: The invention relates to a nut system (100) comprising a nut (104) provided with a main thread (106) with pitch p1 and arranged along a screwing axis (108) of the nut. According to the invention, it also comprises a threaded device (116) coupled in rotation with the nut, this threaded device comprising a secondary non-screwed thread (122) on the main thread (106) from which it is separated, the secondary thread being arranged along the screwing axis and having a pitch p2 different from p1. Application of the invention with a device for resistance of thrusts generated by an aircraft engine.

Abstract: A power tool for fastening objects has a housing with a non-rotatable element, a power drive in the housing and provided with a rotatable driving element, and a fastener part including a bolt having a thread and an axis and introducable into parts forming an object, a nut screwable on the bolt and cooperating with the rotatable driving element, and a washer to be applied between the nut and an object and cooperating with the non-rotatable element, the washer having an axis and being provided with a first bearing face surface located at one axial side and adapted to cooperate with the nut, a second bearing face surface located at an opposite axial side and adapted to cooperate with the object, and at least one third turning resistant surface adapted to cooperate with the thread of the bolt, so that when driving element turns the nut with a given active force in one direction and the washer is held stationarily applied by the non-rotatable element of the housing, the nut turns to tighten or loosen the bolt, and

Abstract: A fastener having an aligning lead thread that does not follow the helical pattern of the fill threads around the shank of the fastener. The aligning lead thread is located on the shank distant from the first full thread to enable the engage the threads of a receiving member to pull the fastener elements into alignment rather than a standard lead thread which becomes trapped behind the threads of a receiving member.

Abstract: A lock nut for engagement with a thread of a bolt, in which a thread block is arranged in the body thereof for engaging with the thread of the bolt and is made eccentric with respect to the axis of the nut body so that an initial tightening force of the nut on the bolt can be held for a long time.

Abstract: An arrangement for detecting a fatigue fracture caused by overstressing of a bolted connection including a bolt and an internal-thread-bearing hollow section which is alternately stressed by an axial flux of force between zero and different maximal values. A transverse crack forms at a predetermined breaking point of the bolted connection, at which the hollow section breaks due to fatigue. The spacing of the predetermined breaking point from the connection ends, and the interaction of the bolt and the hollow section, are designed such that, after the breakage, the bolt forms in the hollow section a residual joining connection which can be alternatingly stressed. In order to signal the occurrence of a crack on the hollow section of the bolted connection in the event of a fracture caused by fatigue in a simple and always noticeable manner, the arrangement has an additional signaling device.

Abstract: A screw having a root and threads formed on the root. The screw is configured to generate and/or maintain axial compression between threads formed in leading and trailing sections of the screw either by virtue of pitch differential in the threads or the way in which the screw is installed.

Abstract: A connector assembly that is subjected to alternating loads by an axial flow of force between zero and various maximum values, with an outer assembly component designed as a hollow section and an inner assembly component located in the outer one and fitting by virtue of its shape. In order to detect failure of the assembly caused by a fatigue fracture produced by overloads at the end point in the assembly direction, even before it develops, in a simple fashion within the functional assembly, the assembly comprises a rear area with play that begins at the end of the connection that points in the assembly direction and a forward zero-play area of the inner assembly component that abuts the latter and is located inside the outer assembly component.

Abstract: The present invention relates to a male and female screw set wherein the male screw comprises at least a projecting part pressing against the flank plane of the female screw when the male and female screws are engaged. A dimensional difference is formed between the pitches of the female and male screw threads. When the female and male screws are engaged, the advancing side flank plane of the female screw thread is contacted by the advancing side flank plane of the male screw thread, while the other receding side flank plane of the female screw thread is contacted by other receding side flank plane of the male screw thread, and these respective flank planes are pressed together with tightening.

Abstract: A fastener and an associated fastening method are provided to securely join at least two structural elements to form a structural assembly. Although the fastener can join a variety of different types of structural elements, the fastener is particularly well adapted to join composite panels, superplastically-formed/diffusion-bonded panels, honeycomb panels and hollow core panels since the fastener can securely join these structural elements without crushing or otherwise damaging the structural assembly. The fastener can also be mounted in blind installations, while providing a relatively smooth head following installation. In addition, the fastener can securely join structural elements while tolerating variations in the thicknesses of the structural elements.

Abstract: Apparatus for securing together structural members includes a stud threaded at both ends and a stud sleeve threaded at both ends. The stud and stud sleeve are coaxial with the stud extending through the stud sleeve and beyond the ends of the stud sleeve. The threaded stud ends and the threaded sleeve ends are separately threadedly connected to the structural members so that both the stud and stud sleeve apply forces to the structural members to secure them together. No significant transfer of load between the stud and the stud sleeve will occur.

Abstract: Self-locking alignment pin and method for aligning a nuclear fuel assembly with respect to a core plate disposed in a nuclear reactor pressure vessel. The fuel assembly has a top nozzle having a first bore formed therein. The core plate has a second bore alignable with the first bore. The second bore has first threads of a first predetermined pitch and second threads of a second predetermined pitch. The alignment pin further includes a shaft that has an end portion having third threads of the first predetermined pitch for threadably engaging the first threads of the second bore. A flange, which has a plurality of recesses in the underside surface thereof, surrounds the shaft and is integrally attached thereto. A locking member surrounds the flange and has exterior fourth threads of the predetermined second pitch for threadably engaging the second threads of the second bore.

Abstract: The fastener, which is especially adapted for bones, consists of a shaft (2) bearing a thread (1) with variable pitch, a front end (3) and a rear end (4).The thread (1) is present over the entire area of the shaft (2), and in the area of the rear end (4) is characterized by a smaller pitch than in the area of the front end (3).Thanks to the diminishing pitch of the thread (1) in the proximal direction, a locally differentiated intraosseous pressure generation takes place. In accord with the well-known Wolff's Law, this leads to a controlled bone growth along the loading axis and thus an improvement in the stability of the implanted fastener.

Abstract: A tamper-proof, self activating nut lock apparatus comprises a threaded shank having an external screw thread of a first pitch and a coaxial threaded bore at one end of the threaded shank, with an internal screw thread of a second pitch, both the said external and internal screw threads having a same direction of rotation. A shank extension having the external pitch of the first pitch and a coaxial threaded projection of the second pitch is screwed into the threaded bore of the shank and a threaded nut is adapted to engage the external threads of the shank and the shank extension. A friction means, such as a nylon insert, is adapted to engage the shank extension and the threaded nut whereby reverse rotation of the nut to remove the nut from the shank without appropriate tools rotates the shank extension for jamming the nut on the threaded shank to prevent removal of the nut.

Abstract: In a rodless cylinder, a moving member which is moved along a cylinder body is reduced in height for the sake of compactness and stability. A stopper is mounted on a stopper support base, which is also reduced in height to preclude the possibilities of obstructing movement of the moving member, and includes a stopper lock mechanism with an adjusting screw suitable for use with the stopper support base of low height. More specifically, in a rodless cylinder having a stopper support base mounted on top of a cylinder body, the stopper support base is provided with inclined surfaces at the opposite ends thereof symmetrically in face to face relation with downwardly-facing inclined surfaces formed on opposite lateral side portions of the cylinder body, and firmly fastened to the cylinder body by setting bolts and clamp members having inclined surfaces face to face with the inclined surfaces.

Abstract: A spacing bolt assembly for securing to a surface includes a cylindrical inner bolt portion having a first end with external threads in a first direction and a second end with a head structure, an outer bolt portion having an axial bore for receiving the inner bolt portion and having a first end with external threads in a second direction and having a second end, and an aperture in the surface containing a central bore segment sized and threaded in the first direction to receive the first end of the inner bolt portion and a counterbore segment sized and threaded in the second direction to receive the first end of the outer bolt portion, so that the outer bolt portion can be screwed into the counterbore segment to a depth leaving a desired exposed length of the outer bolt portion protruding, and the inner bolt portion can be inserted through the axial bore and screwed into the central bore segment until the inner bolt portion head structure abuts and engages with friction the second end of the outer bolt porti

Abstract: A differential screw adjusting mechanism comprised of an externally and internally threaded adjusting nut which has a plurality of slots formed along its length. The internal threads of the adjusting nut cooperatively and threadedly engage screw threads at the end of each of the expansion rods. The rods are in turn fixed to the lip of the die via set screws or jam nuts. A spool having an internally threaded diameter and a slot along its length is engaged to the external threads of the adjusting nut. The head of the spool has a flattened portion to limit rotation of the spool when clamped in place. Thus, the slotted adjusting nut is overfit with the slotted spool. The entire assembly of spool, nut, and rod is clamped in place via a clamping arrangement affixed to the die. The tightening of the clamp serves to close the spool via the slot over the nut, and in turn, the nut, via its slots, over the rod.

Abstract: A fastening apparatus is provided wherein the length of a mating threaded connection between two members is limited as a function of an effective differential pitch to the uniform pitch of the threads on both members whereby clearances of progressive increasing amounts are established between successive opposed tooth flanks. An elastic deformation of one member occurring in a direction opposite to the increasing of the amounts of clearance brings successive opposed flank portions into a force transmitting relationship whereby the total area of flank-to-flank contact between the threads varies as a function of the applied load.

Abstract: A gripping device for tensioning a screwing element (2) which, at its free end, has an outer profile matching the inner profile of an engaging member (4). The screwing element (2) has an outer profile with teeth (20) of constant pitch and of constant cross-section, the mean diameter of which is generated by a truncated cone, and the engaging member (4) has an inner profile with teeth (40) of constant cross-section and of a constant pitch slightly greater than that of the screwing element (2) and generated on a conical bore of the same conicity as the outer profile (20) of the screwing element, the engaging member (4) being provided with a bearing zone (41c) which supports and transmits the forces and which is located on the peripheral part of the latter.

Abstract: A clamp for use in testing machines to prestress a joint between a driving shaft and a driven shaft, both of which are externally threaded with each having a flat surface abutting the other in a plane substantially perpendicular to the driving axis. The clamp is internally threaded to cooperate with the external threads and has bolts which, when tightened, produce a force on the abutting surfaces to compressively preload the joint from forces on the flanks of the external threads.

Abstract: A fatigue resistant threaded connection includes a nut having two threads which are aligned axially but turned relative to one another about their common axis through an angle great enough to cause development of large axial forces between the screw and nut threads when they are connected together, resulting in improved distribution of load forces between the two threads of the nut and improved resistance of the screw and nut to fatigue and tensile failures.

Abstract: The threaded connection is formed between a tapped component and an externally threaded two part bolt. The two bolt parts are each provided with an external thread of the same pitch and hand in order to be threaded simultaneously into the tapped component. One bolt part is also provided with an extension which is threaded into the other bolt part via a screw thread which has an opposite hand or pitch to the external screw threads. When the two bolt part are threaded into the tapped component, the screw threaded extension prevents unthreading of one bolt part relative to the other.

Abstract: A fastener assembly, having a threaded male and female member, is disclosed. One of the members has substantially conventional threads and the other member has two threaded portions rotationally offset relative to one another. Direction of the offset determines whether a compressive or tensile preload force occurs in the assembled fastener. Magnitude of the preload force is controlled by the extent of the offset. One of the threaded portions includes at least two, preferably about four, tapered threads which permit gradual distribution of the preload force and thereby prevent plastic deformation of the threads. The assembled fastener is substantially vibration proof, and, due to the well controlled permanent preload force, is highly fatigue resistant.

Abstract: A connector, for example for connecting a tubular member such as a pipe, comprises a male member which has an external frusto-conical surface provided with a thread and a female member having an internal frusto-conical surface provided with a thread for engagement with the thread of the male member. The members are provided with sealing surfaces which are brought into sealing abutment under an axially directed compressive force when the members are fully engaged together, as a result of which one member, as shown in FIG. 3 the male member, is partly compressed and the other member, as shown in FIG. 3 the female member, is partly tensioned.

Abstract: A connector, for example for connecting a tubular member such as a pipe, comprises a male member which has an external frusto-conical surface provided with a thread and a female member having an internal frusto-conical surface provided with a thread for engagement with the thread of the male member. The members are provided with sealing surfaces which are brought into sealing abutment under an axially directed compressive force when the members are fully engaged together, as a result of which one member is partly compressed and the other tensioned. To improve the load distribution along the threads of the members, the pitch of the thread is varied along the axial length of the threaded surfaces. Specifically the surfaces are divided into three portions, an intermediate portion in which the pitches of the threads of the members are the same, and end portions at either end of the intermediate portion, in which the pitches of the threads differ.

Abstract: The self-locking threaded bearing is an externally threaded tubular member having a discontinuous thread to form thread sections which are spaced-apart axially on the bearing. In the bearing assembly, the thread sections engage portions of an internal thread in a bore of a housing for the bearing and, with the internal thread being more ductile than the thread sections of the bearing, portions of the internal thread are stripped to pack into the space between the thread sections and assist in locking the bearing into the housing.In the method of making the self-locking threaded bearing assembly, a tubular bearing is provided with a discontinuous external thread and a housing is formed with a bore having an internal thread of the same pitch as the external thread of the bearing and of material more ductile than that of the external thread.

Abstract: The device comprises in combination a screwthreaded block and a screw which are hollow and have screwthreads of opposite direction. These screwthreads cooperate with screwthreads of respectively corresponding direction formed in the inner wall of the tapped hole. There are provided means for stopping the block, and means for preventing rotation between the block and the screw.